What is the maximum recommended daily amount of full fat milk for a 12 year old boy, assuming an average weight for 12 year olds at 40kg (88lb). Is 1.5 english pints per day too much?
I have found no credible source that would mention "maximum recommended daily amount of full fat milk."
The US Department of Agriculture recommends the following daily amounts of dairy for children and teens:
- Two through 3 years old: 2 cups (480 milliliters)
- Four through 8 years old: 2½ cups (600 milliliters)
- Nine through 18 years old: 3 cups (720 milliliters)
A 12 year old boy drinking 1.5 US pints (710 milliliters) of milk fits in.
Regarding the concern that milk can make blood acidic: The acidogenic effect of foods can be estimated by "renal acid load" (the amount of acids secreted through the kidneys). According to this article (Table 2), renal acid load after one serving (240 mL) of full fat milk is 3.6, and after low-fat milk 3.9, which means it is not fat in the milk that contributes to the acidity. Renal acid loads of certain other foods are much higher: one serving of cheese (17-57), meat (14-21), fish (10-32), nuts (16-36).
According to one 2015 systematic review, milk consumption does not seem to contribute to kidney stones.
There is an ongoing debate if milk is healthy or unhealthy and there are opinions that milk is only for children (or even only for small children). Most of research shows that milk consumption as such is not bad for health (PubMed Central). On the other hand, plant-based diets may be healthy enough, even for children (PubMed Central).